JP2534298Y2 - Electrostatic coating machine - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to an air motor for rotating a rotary atomizing head at a high speed, the rotary shaft of which is formed by a hollow pipe, and a rotary atomizing head provided at a rear end of a paint supply pipe inserted through the rotary shaft. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic coating machine provided with a coating valve for turning on and off the supply of a coating material, and particularly to a small electrostatic coating machine suitable for mounting on a coating robot.

[0002]

2. Description of the Related Art This type of electrostatic coating machine is widely used for painting an automobile body, etc., and is applicable to painting of a plurality of models carried into a painting line and complicated painting of different painting patterns. Therefore, the demand for a so-called coating robot in which an electrostatic coating machine is mounted on a numerical control robot, a variable sequence robot, or the like having a high degree of freedom is increasing.

However, in a conventional general electrostatic coating machine, a high voltage for coating applied to a rotary atomizing head is supplied by connecting a thick, heavy, high-rigidity high-voltage cable. A high-voltage cable hinders the movement of the manipulator of the painting robot or applies unnecessary load to a servo motor or the like, thereby causing errors in painting or shortening the service life of the robot.

[0004] Further, when the high-voltage cable abnormally approaches a grounded object during the operation of the coating robot, there is also a problem that a leak may occur and a fire or electric shock may occur.

[0005] For this reason, attempts have been made to solve the above-mentioned difficulties by incorporating a small high-voltage generator into an electrostatic coating machine, thereby eliminating the need for connecting a high-voltage cable.

[0006]

However, as shown in FIG. 3, in the conventional electrostatic coating machine, a coating material that is inserted through a pipe-shaped rotary shaft 30 of an air motor 29 and supplies a coating to a rotary atomizing head 31 is used. A needle valve 33 serving as a paint valve is provided in the supply pipe 32, and an air cylinder 34 for opening and closing the needle valve 33 is provided at a rear end side of the paint supply pipe 32. While the valve is closed, a needle valve 36 for opening and closing a paint recirculation passage 35 for recirculating the paint and an air cylinder 37 for driving the needle valve 36 are also provided at the rear end side of the paint supply pipe 32. Pipes 38 for supplying and discharging paint and compressed air to the outside are also connected to the rear.

Therefore, in order to house the high-pressure generator 39 without generating unnecessary projections in the housing 40, it is appropriate to dispose the high-pressure generator 39 behind the pipes 38. Has become very long, making it unsuitable for mounting on a painting robot with a small installation space.

When the needle valves 34 and 36 and the air cylinders 34 and 37 are to be inspected and maintained, the high pressure generator 3
9 and pipes 38 had to be removed, and there was also a major drawback that maintenance was poor.

Therefore, the present invention is to provide an electrostatic coating machine which can be made compact without increasing its length even when a high-pressure generator is installed, and which has good maintenance of paint valves and the like. It is a technical issue.

[0010]

In order to solve this problem, in the electrostatic coating machine according to the present invention, a rotating shaft of an air motor for rotating a rotary atomizing head at a high speed has its tip placed in the rotary atomizing head. An electrostatic coating machine formed of an open hollow pipe and provided with a paint valve for turning on / off the supply of paint into the rotary atomizing head at the rear end of the paint supply pipe inserted through the pipe, The rear end of the paint supply pipe protruding from the rear end of the rotary shaft of the air motor is bent toward the front end in parallel with the rotary shaft of the air motor, and the paint valve provided at the rear end houses the air motor. A small high-pressure generator that is detachably mounted from the front end side of the housing and that applies a high voltage to the rotary atomizing head is mounted in a state of juxtaposition with the air motor.

[0011]

In the electrostatic coating machine according to the present invention, the rear end of the paint supply pipe protruding from the rear end of the rotation shaft of the air motor is bent toward the front end in parallel with the rotation shaft of the air motor. Since the paint valve is provided at the end, the axial dimension can be shortened compared to the conventional electrostatic coating machine, and a small high-pressure generator that applies high voltage to the rotary atomizing head is provided. Since it is mounted side by side with the air motor, the high-pressure generator can be mounted compactly, and can be easily mounted even in a place with a small mounting space, making it ideal for a painting robot.

Further, since the paint valve is detachably mounted from the front end side of the housing containing the air motor, maintenance and inspection of the paint valve and the like are easy even after the paint valve is attached to the painting robot, thereby improving the maintainability. Can be done.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view showing an example of an electrostatic coating machine according to the present invention, and FIG. 2 is a sectional view taken along line AA of FIG.

In FIG. 1, a rotary shaft 3 of an air motor 2 is provided through a rear end surface of a bell 1 forming a rotary atomizing head, and is rotatably supported by an air bearing 5 in a housing 4.

The rotary shaft 3 is formed by a hollow pipe 6 having a tip open into the bell 1, and a paint supply pipe 7 is inserted through the pipe 6 in a non-contact state.

The paint supply pipe 7 has a rear end protruding from the rear end of the rotating shaft 3, as shown in FIG. It is formed in a shape bent in parallel, and a valve seat is formed at its end.

At the rear end of the paint supply pipe 7,
A paint passage 8 is formed, and the paint passage 8 is connected to a paint supply hose (not shown). A paint return passage 9 is connected to the paint passage 8 at right angles.

A paint valve 12 having a needle valve 11 which can be advanced and retracted with respect to a valve seat of the paint supply pipe 7 is detachably mounted in a mounting hole 10 formed at a predetermined position on the distal end side of the housing 4. And a dump valve 1 provided with a needle valve 13 for opening and closing the paint recirculation passage 9.
6 is similarly mounted.

A small high-pressure generator 14 molded with resin is mounted in a mounting hole drilled from the rear end side below the housing 4 in parallel with the air motor 2. The small high-voltage generator 14 converts the voltage of 8 to 24 V supplied by the power cord 15 into a
Those capable of increasing the voltage up to 120 kV are used.

The above is an example of the configuration of the electrostatic coating machine according to the present invention. Since the paint supply pipe 7 is bent in parallel with the rotary shaft 3 from the rear end side of the rotary shaft 3, the axial dimension is shortened. In addition, since the small high-voltage generator 14 is mounted side by side with the air motor 2, the entire apparatus can be made more compact than a conventional high-voltage generator-mounted electrostatic coating machine. Therefore, it can be easily mounted in a place with a small mounting space, and is most suitable for a painting robot.

The small high-voltage generator 14 applies a low voltage of 8 to 24 V to the 80 to 80 V required for coating in the coating machine.
It is very safe because it is boosted to 120KV.
Since the power cord 15 connected to the small high-voltage generator 14 can be made of a lightweight and highly flexible power cord, the power cord 15 does not hinder the movement of the manipulator or the like even when mounted on the painting robot.

The paint valve 12 and the dump valve 1
The needle 6 can be detached from the front end side of the housing 4 so that maintenance and inspection of the needle valves 10, 13 and the like can be easily performed, and the maintenance property is good even in a place where a work space such as a painting robot cannot be widened.

Next, the method of operating the electrostatic coating machine according to the present embodiment will be briefly described. First, the coating machine is attached and fixed to the tip of a manipulator or the like of a coating robot, and the power cord 15 is connected to a constant voltage device or a battery. Connect to In addition,
Other paint supply hoses, paint reflux hoses, air hoses for air motors, air hoses for air bearings, and the like are appropriately connected to the electrostatic coating machine.

When the coating is performed, the air motor 2 is started to rotate the bell 1 at a high speed of about 20,000 to 50,000 rpm, and the small high-pressure generator 14 is started to apply a high voltage of 80 to 120 KV to the bell 1. Is applied.

Next, the paint valve 12 is operated to retract the needle valve 11 from the valve seat of the paint supply pipe 7 to open a paint passage, and paint is supplied to the bell 1 through the paint supply pipe 7. At this time, the paint return path 9 is closed by the needle valve 13 of the dump valve 16. The paint supplied to the bell 1 is atomized and sprayed by centrifugal force and electrostatic force.

When the coating is completed and the washing is performed, the paint valve 12 is operated to close the paint flow path by the needle valve 11, and the dump valve 16 is operated to open the paint recirculation path. Then, the paint supply hose is switched and connected to the supply source of the cleaning solvent and the cleaning air, and the paint return hose is switched and connected to the waste liquid tank. After the paint return path 9 is cleaned, the dump valve 16 is closed and the paint valve 12 is closed. Is opened again to wash and remove the paint remaining in the paint supply pipe 7 and the like.

The shape of the paint supply pipe 7 is not limited to this embodiment, and may be formed into a U-shape. The design of the bending start position and the arrangement of the pipe can be changed as appropriate.
Further, the mounting positions of the small high-pressure generator 14, the coating valve 12, and the like are not limited to the present embodiment, but can be appropriately changed according to the specifications of the coating robot.

[0028]

[Effects of the Invention] As described above, the electrostatic coating machine according to the present invention can shorten the axial dimension compared to the conventional one.
In addition, since the small high-pressure generator is mounted side by side with the air motor, it is possible to reduce the size of the entire coating machine, and there is an excellent effect that it can be easily mounted on a coating robot or the like having a small installation space. .

Further, since the paint valve and the like can be attached and detached from the front end side of the housing, maintenance and inspection are easy, and there is also an effect that the maintainability can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an electrostatic coating machine according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a schematic sectional view showing a conventional electrostatic coating machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Rotary atomization head (bell) 2 ... Air motor 3 ... Rotary shaft 4 ... Housing 7 ... Paint supply pipe 11 ... Needle valve 12 ... Paint valve 14 ... Small high-pressure generator

Claims (1)

(57) [Scope of request for utility model registration] 1. A rotary shaft (3) of an air motor (2) for rotating a rotary atomizing head (1) at a high speed is formed by a hollow pipe (6) having a tip opened into the rotary atomizing head. (6) An electrostatic coating machine provided with a paint valve (12) at the rear end of a paint supply pipe (7) inserted thereinto for turning on / off the supply of paint into a rotary atomizing head (1). The rear end of the paint supply pipe (7) projecting from the rear end of the rotation shaft (3) of the air motor (2) is bent toward the front end in parallel with the rotation shaft (3) of the air motor (2). The paint valve (12) provided at the rear end is detachably mounted from the tip side of the housing (4) containing the air motor (2), and applies a high voltage to the rotary atomizing head (1). The small high-pressure generator (14) to be applied is mounted side by side with the air motor (2). An electrostatic coating machine characterized by being worn.